CIM control design using GRAFCET

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BORANG PENGESAHAN STATUS TESIS·

JUDUL: CIM CONTROL DESIGN USING GRAFCET

SESI PENGA.ITAN: _-,2~O",-04-,,-/;::,;20~O;.:::.5_

Saya SIn RUZAIMAH BINTI RUSIN

(HURUF BESAR)

mengaku membenarkan tesis (SmjtttIti !kMu/Sarjana IDOIeIOl fltlsahth)* ini disimpan di Perpustakaan dengan syarat-syarat kegunaan seperti berikut:

1. Tesis adalah hakmilik Kolej Universiti Teknologi Tun Hussein Onn. 2. Perpustakaan dibenarkan membuat salinan untuk tujuan pengajian sahaja.

3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi pengajian tinggi.

4. **Sila tandakan (..r)

D

D

(Mengandungi maklumat yang berdarjah keseJamatan atan kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMl1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasilbadan di mana penyelidikan dijalankan)

II ,/ II

;Kyf"

(TANDATANGAN PENULIS)

Ala mat Tetap:

KM 18 KG SERKAM PANTAI,

MERLIMAU,

PM. DR. ZAlNAL ALAM HARON

77300 MELAKA. Nama Penyelia Tarikh: 1 APRIL 2005 Tarikh: 1 APRIL 2005

CATATAN: _*

**

•

Potong yang tidak berkenaan.

Jika tesis ini SULIT atau TERHAD, siIa lampirkan sumt daripada pihak berkuasaiorganisasi berkenaan dengan menyatakan sekali tempoh tesis ini perlu dikelaskan sebagai atau TERHAD.

Tesis dimaksudkan sebagai tesis bagi Ijazah dol-tor Falsafah dan Srujana secara Penyelidikan, atau disertasi bagi pengajian secam kerja kurslL~ dan

" I hereby declare that I have read this thesis and acknowledge it has achieved the scope and quality for the award of the Degree of Master of Electrical Engineering."

Signature Supervisor Date

I

I .

' -... ~ ... .

SITI RUZAIMAH BINTI RUSIN

A thesis submitted in partial fulfillment of the requirements for the award of the Degree of Master of Engineering (Electrical)

Kolej Universiti Teknologi Tun Hussein Onn

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"No part of the study was covered by copyright. References of information obtained from other sources are specially quoted; otherwise the rest of the information presented

through this study is solely worked and experimentally carried out by the author"

Signature

... -J+!l ... .

Author SIn HUZAIMAH HUSIN

For you, my mom and dad

For your tnt/y support and undivided love

For making me the person

IV

ACKNOWLEDGEMENT

I would like to take this great opportunity to extend my deepest gratitude to all these who have assisted me in making this project a success. A special note ofthanks goes to my respected supervisor, Assoc. Prof. Dr Zainal Alam Haron for his patience and guidance throughout the course of this project.

I would also like to take this opportunity to thanks all technicians who have played a role in accomplish this project.

ABSTRACT

This project is concerned with learning and exploring industrial automation technologies, such as control systems, Computer Integrated Manufacturing system and the relationship between these major components. The CIM70A System will be used in this project and located at Automation Lab, Kuithho. The project is divided into two major parts. In the first part, the author familiarized herself with the operation and all the functions of the related industrial components ofthe CIM70A System, such as the sensors, actuators, and the valves. In the second part, the author aimed to study

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CONTENTS

CHAPTER TITLE _PAGE

ACKNOWLEDGEMENT IV

ABSTRACT V

CONTENTS vi

LIST OF TABLES IX

LIST OF FIGURES X

LIST OF APPENDICES Xlll

I INTRODUCTION

1.1 Background

1.2 Problem Statement 3

l.3 Objectives of Project 4

II LITERATURE REVIEW

2.1 Introduction 5

2.2 Historical Development 7

IV PROGRAMMABLE LOGIC CONTROLLER

4.1 Introduction ₁₂

4.2 PLC Hardware Design ₁₄

4.3 Using and Understanding Ladder Diagrams

4.3.1 Electrical Diagram 17

4.3.2 Ladder Diagram Rules 20

V GRAFCET

5.1 Background Of GRAFCET 25

5.2 Why use GRAFCET? 26

5.3 Basic Notions 28

5.4 GRAFCET Examples 45

VI PROJECT FINDINGS AND DISCUSSION PART 1

6.1 Introduction 52

6.2 Architecture ofthe CIM70A system 54

6.3 Manufacturing system design of CIM70A 55 6.4 Characteristics of the conveyor system

6.4.1 Basic Conveyor System 55

6.4.2 Pallet Positioner 56

6.4.3 Pallet Transfer 57

6.5 The Station of CIM70A

6.5.1 ASRS 58

6.5.2 Pin Insertion Station 59

6.5.3 Assembly Station (Pick & Place) 60 6.5.4 Vision Inspection Station 61

6.6 Supervisory of the CIM70A System 61

6.7 Communication Network 64

V 111

VII PROJECT FINDINGS AND DISCUSSION PART II

7.1 Introduction 68

7.2 Revision ofGRAFCET Basic Notations 69

7.3 The implementation ofGRAFCET 72

7.3.1 Modeling the CIM70A system using GRAFCAT 73 7.3.2 Modeling the module Assembly Station of

CIM70A using GRAFCET 75

VIII CONCLUSION AND SUGGECTION 79

REFERENCES 81

APPENDIX A: LIST OF COMPONENTS OF CIM70A 83 APPENDIX B: CIM70A CONTROL PANEL SOFTWARE 88

APPENDIX C: CITECT SCADA SOFTWARE 90

APPENDIX D: PLC LINK MEMORY CONFIGURATIONS 92

APPENDIX E: GRAFCET TUTORIAL 98

APPENDIX F: PROGRAM CONTROL DESIGN USING

GRAFCET 115

LIST OF TABLES

TABLE NO. TITLE PAGE

5.1 Description of Example 2 47

5.2 Description of Example 3 48

5.3 Description of Example 4 49

6.1 The Functions of Citect SCADA, CIM70A 62

x

LIST OF FIGURES

FIGURE NO. TITLE PAGE

3.1 The Project Process Flow 10

4.1 Programmable controller clock diagram 14

4.2 Product sensed as in position on the conveyor 15

4.3 Wiring Diagram 18

4.4 Ladder Diagram 18

4.5 Simplified Ladder Diagram 19

4.6 Three Rung Ladder Diagram 21

4.7 Two Switches Wired in Series 22

4.8 The Truth Table for Series Devices 23

4.9 Two Switches Wired in Parallel 23

4.10 The Truth Table for Parallel Devices 24

5.1 Representation of a Step 28

5.2 Representation of a transition 29

5.3 Representation of directed links 30

5.4 Evolution of GRAFCET 31

5.8 Illustration of simultaneous firing 36

5.9 Illustration of Level Action 37

5.10 Illustration of Impulse Action 38

5.11 Logic Controller, inputs, actions and outputs 39

5.12 Concurrency and synchronization 40

5.13 Internal State and time 41

5.14 Macrostep 43

5.15 Forcing Action 44

5.16 Simple Movement of Cylinder 45

5.17 GRACFET for Example 1 46

5.18 Extend and retract movement of a cylinder 46

5.19 GRAFCET for Example 2 47

5.20 GRAFCET for Example 3 48

5.21 GRAFCET for Example 4 49

5.22 Two Cylinders movement 50

5.23 GRAFCET for Example 5 51

6.1 Automated workce1l of CIM70A system 53

6.2 Pyramid of Automation 54

6.3 Conveyor line 58

6.4 ASRS 59

6.5 Pin Insertion Station 60

6.6 Assembly Station 60

6.8

6.9

7. I

7.2

7.3

Serial PLC Link Network Setup

Connection between 4 controllers using RS 485

GRAFCET ofCIlv!70A system

Assembly Station of CIlv!70A system

The GRAFCET of Assembly Station ofCE\170A

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LIST OF APPENDICES

APPENDIX NO. TITLE PAGE

A LIST OF COMPONENTS OF CIM70A 83

B CIM70A CON1ROL PANEL SOFTWARE 88

C CITECT SCADA SOFTWARE 90

D PLC LlNK MEMORY CONFIGURATION 92

E TUTORIAL ON GRAFCET 98

F CON1ROL PROGRAM DESIGN USING GRAFCET 115

CHAPTER I

INTRODUCTION

1.1 Background

for designing, programming and describing logic sequential control systems. TIlis powerful graphical language dedicated to the specification of the behavior of sequential logical systems. It is standardized by CEl and its semantic is defined for this type of applications. The [1] and [2], concluded that thc GRAFCET is a very good tool for logic controller specification, and the graphical nature of the language makes GRAFCET easy to learn and use.

With a tremendous number of inputs and outputs, the model of the control system or application has typically over fifty steps and transitions and therefore, it is difficult for a human operator to understand it; the GRAFCET formalism loses one of its major qualities namely to provide a graphical representation model of the sequential model [3].

GRAFCET also has contributions in design recovery for relay ladder logic. The objective in design recovery is to analyze existing source code and construct from it a structured representation of the program logic. In [4], it has been proved that an existing RLL programs can be translate into GRAFCET that clearly represents the sequential control logic rclative to the specified process control application.

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1.2 Problem Statement

Dealing with the computer integrated manufacturing system, we will involve with a great number of programmable logic controller as its workhorse. Many existing programs for the PLCs are written in relay ladder logic (RLL), which in its most primitive form is a graphical representation of Boolean switching functions based on an analogy to physical relay systems. Although RLL is widely used and understood by industry technical person, the RLL is often difficult to debug and modify because its graphical representation of switching logic makes ordinary person difficult to understand the sequential in the program design.

Furthermore, there is no formality in order to design the control system. There is one approach that commonly used in order to develop the control program using PLC. Namely, try and error approach or heuristics approach, which will be differed from one designer to other. Besides, this unstructured approach will not guarantee the safety, the working, the readability and understanding of the operation of the system.

Haw to represent the logic controller systems in aformalway?

1.3 Objectives of Project

This project is consisted of two parts. In the Part I, the objectives of this work. is to familiarize with the system itself, the function and the controlling elements. Since the PLC as the controller, the CX Programmer as the programming tool will also be learned in this part.

For Part II, the objective is to write the programming using the GRAFCET as a graphical tool in order to develop the working control program that in lined with the existing system. In further, the objective is to provide a set oflaboratory manual how to start and use GRACET as a design tool as a references materials for the students or lecturers for future work. As mentioned above, the main objective of this paper is, to design the CIM70A system control program using the GRAFCET that clearly represents the sequential control logic relative to the specified process control application. Also to show that GRAFCET can be used as a design tool that can helps the designers to come out with the structured, safety, working and readability control program.

CHAPTERll

LITERATURE REVIEW

2.1 Introduction

The cost of developing software for the logic controller in the manufacturing world become increasing by a day. Furthermore, in designing the representation of the logic controller such as PLC, many companies using a different languages. In the desire to improve the capabilities of this logic controller, these languages become more complex. This is in contradiction with the main goals of the PLCs, which is that the PLC is a very simple system because it is very important that PLC must be reliable. There obviously needs to be a consistent philosophy for developing reusable code for manufacturing controllers systems.

In today's economic contexi, the design of these control applications is of a great impact in terms of productivity and production costs. Because of these costs, of the complexity of the control systems and the multiple hardware/software

combinations, the designer has to take the safety of these systems into account. In

methods will help the designer to troubleshoot the programs while the error occurs in the production.

One way is to ensure the safety of the PLC programs is by using "framework" or standard while programming process began.

As concluded in [1], the usage of Grafcet as a very good tool for logic controller specification has been approved. It allows modeling of concurrency and synchronization. Above all, the input-output behavior is specified without doubt. When some parts of the logic controller can be described separately, one can use macrosteps to simplify the model. Also, the comparison was made between State Table, Petri Net, RLL and Grafcet, and it make an evident that the Grafcet applications was the easiest among all.

The strength of the Grafcet also had shown in [2]. The graphical nature of the language makes Grafcet easy to learn and use. The ability to test different ideas quickly has been very useful in determining the fmal design. The Grafcet helps the designer determine: modularization of the code, functions that can be performed in parallel, communication between parallel processes, and problems in control flow. The further extension of the Grafcet usage has been proved in [3], which touched on how this tool can be applied to the reduction of a model in a specific context such as for the model that has typically over fifty steps and transitions. The Grafcet also has been successful in [4] in order to converting existing RLL programs into the form that considerably easier to understand and it also helps to modify the programs.

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PLC can avoid human errors and can indicate on a set of outputs, the parts and variables of the plant that do not satisfy the interaction demand conditions. In order to make the Grafcet success, [10] introduced two different techniques to make proofs on the properties of this language.

2.2 Historical Development

In 1975, the working group called "Logical Systems" from AFCET (Association Franyaise de Cybemetique Economique et Technique) create the standardisation of a requirement representation for a logical automated system. This group trying to defIne a simple formalism, accepted by everyone and well-adapted for the representation of the sequential evolutions of a system understandable by designers as well as by users and providing potentially easiness for the

implementation with hardware and/or software solutions. In December 1977, the Grafcet which means Functional Graph of a Step-Transition Command was derived as a tool of state graphs. After Grafcet had been introduced in higher and technical education, it was supported by the arrival of the fIrst programming languages allowing implementation of Grafcet specification models on industrial logic controllers; it became an AFNOR standard in 1982 known under the reference NF C03190.

Aware of the necessity to precise how to implement a Grafcet specifIcation with hardware and/or software, a synthesis document on recommended

interpretations for the transformation from the Grafcet specification model to a specifIc realization. This thought led the group to propose in 1987 in an AFCET synthesis document, a certain number of Grafcet ex1:ensions to meet users'